3
4.1V 86B429
D1
R2
C
C3
1
3
2
P1
L1
2
.6V .1V
.05V
3.5V
D2
86A415
Q1
86A348
R1
R6
C5
33K
Q2
86A350
150 pF
24K
R5
62K
150 pF
C8
C7
1.9V
.1V
B
C6
R4
360K
.047,5%
33X6.3
.047,5%
.05V
BRN
C2
C1
L2
3
1
150 pF
150 pF
YEL
GRNBLK
WHT
1. ALL RESISTORS 5%,1/8 WATT, UNLESS OTHERWISE SPECIFIED.
A
NOTES:
2. ALL NON–POLAR CAPACITORS IN µF, TOLERANCE 10% AND 50 VOLTS OR MORE
UNLESS OTHERWISE SPECIFIED. POLARIZED CAPACITORS SHOWN IN µF x VOLTS.
T1
D.C. VOLTAGE
A.C. VOLTAGE
3. D.C. VOLTAGES MEASURED WITH 11 MEG INPUT VOLTMETER; A.C. VOLTAGE MEA-
SURED WITH 1 MEG INPUT VOLTMETER. VALUES SHOWN ARE TYPICAL AND MAY
VARY ± 20%.
4. THE FOLLOWING SYMBOLS DENOTE:
CASE GROUND
CIRCUIT BOARD GROUND
13
2
RED
BLK
GRN
4
P2
5. POWER SOURCE IS 21 VDC THROUGH TWO 1.691 KOHM, 1% RESISTORS FROM
SUPPLY TO PINS 2 AND 3 OF CONNECTOR P1.
6. INPUT SIGNAL OF 0.1V AT 2 KHZ
APPLIED TO CIRCUIT BELOW:
.1V
A
B
C
18K
1.2K
10x10

FURNISHED ACCESSORIES

Preamplifier (SM93) ..................................................... 90A4360

Black Windscreen (WL93, SM93) .............................RK355WS*

Black Tie Clip Assembly (WL93, SM93) ....................RK354SB*

Dual Black Tie Clip Assembly (SM93) ........................RK307DB

Tan Windscreen (WL93T) ..........................................RK304T**

Tan Tie Clip Assembly (WL93T)..................................RK304T**

Black Sew-on Mounting Bracket (WL93, SM93).......... 65B1733

Tan Sew-on Mounting Bracket (WL93T) ....................65B1733A

Zippered Carrying Bag..................................................... 26A13

*Replacements furnished in multiples of 4.
** RK304 includes 2 tie clips and 2 windscreens.

OPTIONAL ACCESSORIES

In-Line On/Off Switch...................................................... WA360

CERTIFICATION

Eligible to bear CE Marking. Conforms to European EMC Directive

89/336/EEC. Meets applicable tests and performance criteria in

European Standard EN 55103 (1996) parts 1 and 2, for residential

(E1) and light industrial (E2) environments.

TEST CIRCUIT

FIGURE 3

TYPICAL FREQUENCY RESPONSE

FIGURE 4

OVERALL DIMENSIONS

FIGURE 5

1
2
4
3
+5V
20 K
V out
2.2 F
500 1,000 2,000 5,000 10,000 20,00050 100 20020
0
+10
–10
SM93

Bd

Hz

0.23 IN.
(5.84 mm) 0.24 IN.
(6.10 mm)
0.37 IN
(9.40 mm)
0.15 IN.
(3.81 mm)
(1–1/16 IN.)
27 mm
(3–29/32 IN.)
18.8 mm
(3/4 IN.)
SM93 PREAMPLIFIER SM93/WL93 MICROPHONE
98.8 mm

SM93 PREAMPLIFIER CIRCUIT DIAGRAM

FIGURE 6